0015.3Sum.go

 package main
 
 	
import ( 
    "sort"
)
func threeSum(nums []int) [][]int {
    res := [][]int{}
    //corner case
    if nums == nil || len(nums) < 3 {
        return res
    }
    sort.Ints(nums)
    
    for i := 0; i < len(nums) - 2; i++ {
        if i > 0 && nums[i] == nums[i-1]{
            continue
        }
        left, right := i+1, len(nums) - 1
        for left < right{
              sum := nums[i] + nums[left] + nums[right]
              if sum == 0 {
                  temp := make([]int, 3)
                  temp[0] = nums[i]
                  temp[1] = nums[left]
                  temp[2] = nums[right]
                  res = append(res, temp)
                  for left < right && nums[left] == nums[left+1] {
                      left += 1
                  }
                  for left < right && nums[right] == nums[right-1]{
                      right -= 1
                  }
                  left += 1
                  right -= 1
              } else if sum < 0 {
                  left += 1
              } else {
                  right -= 1
              }
        }
    }
    return res
}